Image Processing to Retain Small Color/Gray Differences

1. A method for encoding an image, comprising: receiving the image; adjusting the image based on a global uniform macro-type color space; modifying a portion of the image spatially based on a local uniform micro-type edge characteristic comprising a just-noticeable difference (JND) between a pixel of the portion and at least one neighboring pixel; converting, before the modifying of the portion of the image, the image from a first global uniform macro-type color space into a second global uniform macro-type color space; converting, after the modifying of the portion of the image, the image from the second global uniform macro-type color space into the first global uniform macro-type color space, wherein the local uniform micro-type edge characteristic is in the second global uniform macro-type color space; and outputting the image.

2. The method of claim 1 , wherein the image comprises at least one of monochrome image and color image.

3. The method of claim 1 , wherein the global uniform macro-type color space comprises at least one of sRGB, Adobe RGB, CIE L*a*b*, and CIE L*u*v*.

4. The method of claim 1 , further comprising: enhancing an edge by a first predefined amount when the edge is smaller than a first predefined parameter; and reducing an edge by a second predefined amount when the edge is larger than a second predefined parameter.

5. The method of claim 4 , wherein when a setting of a brightness level of a display device is changed, the first predefined parameter and the second predefined parameter are changed.

6. The method of claim 4 , wherein when a setting of a brightness level of a display device is changed, the first predefined amount and the second predefined amount are changed.

7. A non-transitory computer readable medium (CRM) storing instructions for encoding an image, the instructions comprising functionality for: receiving the image; adjusting the image based on a global uniform macro-type color space; modifying a portion of the image spatially based on a local uniform micro-type edge characteristic comprising a just-noticeable difference (JND) between a pixel of the portion and at least one neighboring pixel; converting, before the modifying of the portion of the image, the image from a first global uniform macro-type color space into a second global uniform macro-type color space; converting, after the modifying of the portion of the image, the image from the second global uniform macro-type color space into the first global uniform macro-type color space, wherein the local uniform micro-type edge characteristic is in the second global uniform macro-type color space; and outputting the image.

8. The CRM of claim 7 , wherein the image comprises at least one of monochrome image and color image.

9. The CRM of claim 7 , wherein the global uniform macro-type color space comprises at least one of sRGB, Adobe RGB, CIE L*a*b*, and CIE L*u*v*.

10. The CRM of claim 7 , wherein the instructions further comprise functionality for: enhancing an edge by a first predefined amount when the edge is smaller than a first predefined parameter; and reducing an edge by a second predefined amount when the edge is larger than a second predefined parameter.

11. The CRM of claim 10 , wherein when a setting of a brightness level of a display device is changed, the first predefined parameter and the second predefined parameter are changed.

12. The CRM of claim 10 , wherein when a setting of a brightness level of a display device is changed, the first predefined amount and the second predefined amount are changed.

13. A device for encoding an image, comprising: a first memory that receives an image; an image adjustment section that adjusts the image based on a global uniform macro-type color space; an image modification section that modifies a portion of the image spatially based on a local uniform micro-type edge characteristic comprising a just-noticeable difference (JND) between a pixel of the portion and at least one neighboring pixel; and a second memory that receives an output image, wherein the image adjustment section: before the modifying of the portion of the image, converts the image from a first global uniform macro-type color space into a second global uniform macro-type color space; and after the modifying of the portion of the image, converts the modified image from the second global uniform macro-type color space into the first global uniform macro-type color space, wherein the local uniform micro-type edge characteristic is in the second global uniform macro-type color space.

14. The device of claim 13 , wherein the image comprises at least one of monochrome image and color image.

15. The device of claim 13 , wherein the global uniform macro-type color space comprises at least one of sRGB, Adobe RGB, CIE L*a*b*, and CIE L*u*v*.

16. The device of claim 13 , wherein the image modification section: enhances an edge by a first predefined amount when the edge is smaller than a first predefined parameter; and reduces an edge by a second predefined amount when the edge is larger than a second predefined parameter.

17. The device of claim 16 , wherein when a setting of a brightness level of a display device is changed, the first predefined amount and the second predefined amount are changed.